Penicillin Sensitivity of Strains of Non-hemolytic Streptococci Isolated from Gases of Sub-acute Bacterial Endocarditis

With occasional exceptions strains of non-hemolytic streptococci isolated from cases of sub-acute bacterial endocarditis are sensitive to penicillin in vitro. The degree of sensitivity is approximately the same as that shown by strains of staphylococci isolated from human infections but is not as great as that exhibited by hemolytic streptococci. The degree of sensitivity of any particular strain does not correspond with the cultural or serological properties of the strain. In the treatment of each individual case, the sensitivity of the infecting strain should be determined as a guide to appropriate therapy.